| Nutrition and
Vitamins for Your Eyes Vitamin A and Other Carotenoids How much vitamin A do you need? The U.S. RDA (recommended daily allowance) for males age 11+ is 1,000 Retinol Equivalents (RE); the RDA for females age 11+ is 800 RE. Vitamin A is also measured in International Units (IU): 1 RE = 10 IU for plant products and 1 RE = 3.3 IU for animal products. If you smoke or drink, plan on taking in extra vitamin A, because tobacco keeps your body from absorbing it and drinking depletes what you already have in your body. However, watch out for beta-carotene supplements: studies suggest that they increase smokers' incidence of lung cancer. Instead, get your vitamin A from food sources. You can get vitamin A from two types of food sources:
animal products that contain vitamin A (such as liver or butter) or plant
products that contain carotene, which your body converts into vitamin
A. Foods containing carotene are usually yellow/orange or leafy and green.
The following is a sampling of foods with high vitamin A values:
Food RE in The above values are for raw foods. Cooking can change the values, as heat will destroy vitamin A and beta-carotene in foods. Also, if you don't pick up fresh food, select frozen rather than canned, as canning strips away much more of the vitamin A in food. Lutein and zeaxanthin are closely related: they often appear together in fruits and vegetables, and your body can convert lutein into zeaxanthin. There is currently no RDA for either, but you need to get some every day, because your body can't make them. The best source of lutein and zeaxanthin is green, leafy vegetables, particularly spinach. Kale and collard greens are also good choices. You can also find lutein and zeaxanthin in yellow and orange fruits and vegetables, such as corn. By the way, the Lutein Information Bureau says that cooked vegetables are a better source of lutein than raw, as cooking breaks down the cell walls to release the lutein. Studies suggest that high levels of vitamin C can reduce
the risk of cataracts, which are caused by a buildup of protein that results
in cloudy vision. Antioxidant vitamins C and E may also play a role in
delaying age-related macular degeneration, which currently has no cure. A: Presbyopia is a fact of life for everyone. It usually
begins in your 40s. There are no vitamins, herbs or eye exercises that
can make it go away. There is some research being done on surgical cures,
but the results are pending. Read more about presbyopia. So how much vitamin C should you be getting? The U.S. RDA is 60 milligrams (mg) for both males and females. You should absolutely get the RDA every day. Not only are humans unable to create their own vitamin C (unlike most other species), but we also can't store it in our bodies for very long. If you smoke, drink or have diabetes, you should try to take in extra vitamin C, because your levels will tend to be lower than average. Citrus fruits, berries, peppers, tropical fruits, potatoes and green, leafy vegetables have a lot of vitamin C. Here's a sampling: Food mg in The above values are for raw foods. Cooking can change the values, as heat will decrease the vitamin C content. Light is also destructive to C, so if you drink orange juice, it's better to purchase it in opaque plastic jugs or cartons, rather than in glass bottles. Like vitamin A, foods with C are better fresh than frozen or canned, as either process could deplete the amount of the vitamin. Bilberry is the source of bioflavonoids most often touted as being good for your eyes, but it's not very common in the United States. The white part in the center of citrus fruits is an excellent source of bioflavonoids, and you can also get them from red and purple fruits, such as cherries, grapes and plums. Buckwheat is another good source. You may sometimes hear bioflavonoids referred to by their many specific names, including: quercetin, rutin, hesperidin or the subgroup anthocyanosides. How much vitamin E do you need? The U.S. RDA for males aged 11+ is 10 mg; for females aged 11+, it's 8 mg. As with both A and C, if you smoke, you should plan to consume extra vitamin E. Nuts are your best source of vitamin E. Here's a sampling of foods that are high in E: Food mg in Bear in mind that all antioxidants are good for your body,
including your eyes, but vitamins A, C and E and lutein are the most helpful
to your eyes. |
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